?What Are Viruses
What are viruses Viruses are present allover around us. A virus is a very small particle that can cause a disease when infecting the cells of a living organism. They are obligate intracellular microorganisms i.e living only inside the cells of the living host. Structure of the virus The structure of Viruses The single unit of viruses is called a viron and it's composed of : - Nucleic acid (NA): which carries the genetic material of the virus. It's either DNA or RNA. Viruses are classified broadly according to the type of genetic material they have into DNA and RNA viruses. - Capsid : the capsid is the protein coat that surrounds the NA and protects it. It's consists of smaller subunits called capsomers. The capsid acts as a protective container for the most important part of the virus; the nucleic acid. - Envelope: made up of lipid or lipoprotein derived from the nuclear or cytoplasmic membranes of the host cells. It's not present i